A phosphor is essential for a vacuum ultraviolet excited light-emitting device such as plasma display panel (PDP) and rare gas lamp. Various phosphors have been developed. For instance, as the phosphor which is excited by irradiating with a vacuum ultraviolet to emit green light, aluminate represented by BaAl12O19:Mn and silicate represented by Zn2SiO4:Mn are known and these phosphors are widely used.
The vacuum ultraviolet excited light-emitting device includes, for instance, a front plate; a rear plate; a barrier rib between the front plate and the rear plate, which is contacted to each plate; an electrode generating electric discharge in spaces surrounded by the front plate, the rear plate and the barrier rib; a phosphor layer formed on the inside surface of the barrier rib, the front plate or the rear plate, further, a rare gas charged in the spaces. In the vacuum ultraviolet excited light-emitting device, plasma is generated through the electric discharge in the spaces filled with the rare gas to emit vacuum ultraviolet, and then the phosphor layer is excited by irradiation with the vacuum ultraviolet to emit visible light (for instance, green light).
In such a vacuum ultraviolet excited light-emitting device, since the phosphor is exposed to the plasma, there has been desired the phosphor having small reduction in brightness when exposed to the plasma.